Modern bottling practice includes the step of loading bottles on a conveyer and advancing them, sometimes at rates up to 2000 bottles per minute, to a filling station where they are charged with a liquid, say a beverage. It is known that oxidation causes beverages such as beer to deteriorate. It is therefore desirable to minimise the contact between the beer and the oxygen of the atmosphere during bottling of the beer. It is therefore desirable to flush the empty bottles with a non-oxidising gas such as nitrogen so as to reduce the concentration of oxygen in the gaseous atmosphere they contain. Known proposals for performing this flushing step involve passing the bottles from the conveyer line to a station at which they can be flushed with nitrogen. The station normally comprises a carousel which receives bottles from a first line and returns the duly flushed bottles to a second line. This procedure has two disadvantages. First, the requirement for the carousel or other station at which the bottles can be flushed with nitrogen adds appreciably to the total capital cost of the bottling plant. Second, it increases the duration of the bottling procedure.
There is thus a need for a method and apparatus which may be used to flush the bottles with a suitable gas while they are being conveyed along a straight line path, and which preferably do not require a large capital expenditure. It is an aim of the present invention to provide an apparatus and a method that meet this need.